<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Db
 * @subpackage Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Ibm.php 16203 2009-06-21 18:56:17Z thomas $
 */


/** @see Zend_Db_Adapter_Pdo_Abstract */
require_once 'Zend/Db/Adapter/Pdo/Abstract.php';

/** @see Zend_Db_Abstract_Pdo_Ibm_Db2 */
require_once 'Zend/Db/Adapter/Pdo/Ibm/Db2.php';

/** @see Zend_Db_Abstract_Pdo_Ibm_Ids */
require_once 'Zend/Db/Adapter/Pdo/Ibm/Ids.php';

/** @see Zend_Db_Statement_Pdo_Ibm */
require_once 'Zend/Db/Statement/Pdo/Ibm.php';


/**
 * @category   Zend
 * @package    Zend_Db
 * @subpackage Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Db_Adapter_Pdo_Ibm extends Zend_Db_Adapter_Pdo_Abstract
{
	/**
	 * PDO type.
	 *
	 * @var string
	 */
	protected $_pdoType = 'ibm';

	/**
	 * The IBM data server connected to
	 *
	 * @var string
	 */
	protected $_serverType = null;

	/**
	 * Keys are UPPERCASE SQL datatypes or the constants
	 * Zend_Db::INT_TYPE, Zend_Db::BIGINT_TYPE, or Zend_Db::FLOAT_TYPE.
	 *
	 * Values are:
	 * 0 = 32-bit integer
	 * 1 = 64-bit integer
	 * 2 = float or decimal
	 *
	 * @var array Associative array of datatypes to values 0, 1, or 2.
	 */
	protected $_numericDataTypes = array(
	Zend_Db::INT_TYPE    => Zend_Db::INT_TYPE,
	Zend_Db::BIGINT_TYPE => Zend_Db::BIGINT_TYPE,
	Zend_Db::FLOAT_TYPE  => Zend_Db::FLOAT_TYPE,
                        'INTEGER'            => Zend_Db::INT_TYPE,
                        'SMALLINT'           => Zend_Db::INT_TYPE,
                        'BIGINT'             => Zend_Db::BIGINT_TYPE,
                        'DECIMAL'            => Zend_Db::FLOAT_TYPE,
                        'DEC'                => Zend_Db::FLOAT_TYPE,
                        'REAL'               => Zend_Db::FLOAT_TYPE,
                        'NUMERIC'            => Zend_Db::FLOAT_TYPE,
                        'DOUBLE PRECISION'   => Zend_Db::FLOAT_TYPE,
                        'FLOAT'              => Zend_Db::FLOAT_TYPE
	);

	/**
	 * Creates a PDO object and connects to the database.
	 *
	 * The IBM data server is set.
	 * Current options are DB2 or IDS
	 * @todo also differentiate between z/OS and i/5
	 *
	 * @return void
	 * @throws Zend_Db_Adapter_Exception
	 */
	public function _connect()
	{
		if ($this->_connection) {
			return;
		}
		parent::_connect();

		$this->getConnection()->setAttribute(Zend_Db::ATTR_STRINGIFY_FETCHES, true);

		try {
			if ($this->_serverType === null) {
				$server = substr($this->getConnection()->getAttribute(PDO::ATTR_SERVER_INFO), 0, 3);

				switch ($server) {
					case 'DB2':
						$this->_serverType = new Zend_Db_Adapter_Pdo_Ibm_Db2($this);

						// Add DB2-specific numeric types
						$this->_numericDataTypes['DECFLOAT'] = Zend_Db::FLOAT_TYPE;
						$this->_numericDataTypes['DOUBLE']   = Zend_Db::FLOAT_TYPE;
						$this->_numericDataTypes['NUM']      = Zend_Db::FLOAT_TYPE;

						break;
					case 'IDS':
						$this->_serverType = new Zend_Db_Adapter_Pdo_Ibm_Ids($this);

						// Add IDS-specific numeric types
						$this->_numericDataTypes['SERIAL']       = Zend_Db::INT_TYPE;
						$this->_numericDataTypes['SERIAL8']      = Zend_Db::BIGINT_TYPE;
						$this->_numericDataTypes['INT8']         = Zend_Db::BIGINT_TYPE;
						$this->_numericDataTypes['SMALLFLOAT']   = Zend_Db::FLOAT_TYPE;
						$this->_numericDataTypes['MONEY']        = Zend_Db::FLOAT_TYPE;

						break;
				}
			}
		} catch (PDOException $e) {
			/** @see Zend_Db_Adapter_Exception */
			require_once 'Zend/Db/Adapter/Exception.php';
			$error = strpos($e->getMessage(), 'driver does not support that attribute');
			if ($error) {
				throw new Zend_Db_Adapter_Exception("PDO_IBM driver extension is downlevel.  Please use driver release version 1.2.1 or later");
			} else {
				throw new Zend_Db_Adapter_Exception($e->getMessage());
			}
		}
	}

	/**
	 * Creates a PDO DSN for the adapter from $this->_config settings.
	 *
	 * @return string
	 */
	protected function _dsn()
	{
		$this->_checkRequiredOptions($this->_config);

		// check if using full connection string
		if (array_key_exists('host', $this->_config)) {
			$dsn = ';DATABASE=' . $this->_config['dbname']
			. ';HOSTNAME=' . $this->_config['host']
			. ';PORT='     . $this->_config['port']
			// PDO_IBM supports only DB2 TCPIP protocol
			. ';PROTOCOL=' . 'TCPIP;';
		} else {
			// catalogued connection
			$dsn = $this->_config['dbname'];
		}
		return $this->_pdoType . ': ' . $dsn;
	}

	/**
	 * Checks required options
	 *
	 * @param  array $config
	 * @throws Zend_Db_Adapter_Exception
	 * @return void
	 */
	protected function _checkRequiredOptions(array $config)
	{
		parent::_checkRequiredOptions($config);

		if (array_key_exists('host', $this->_config) &&
		!array_key_exists('port', $config)) {
			/** @see Zend_Db_Adapter_Exception */
			require_once 'Zend/Db/Adapter/Exception.php';
			throw new Zend_Db_Adapter_Exception("Configuration must have a key for 'port' when 'host' is specified");
		}
	}

	/**
	 * Prepares an SQL statement.
	 *
	 * @param string $sql The SQL statement with placeholders.
	 * @param array $bind An array of data to bind to the placeholders.
	 * @return PDOStatement
	 */
	public function prepare($sql)
	{
		$this->_connect();
		$stmtClass = $this->_defaultStmtClass;
		$stmt = new $stmtClass($this, $sql);
		$stmt->setFetchMode($this->_fetchMode);
		return $stmt;
	}

	/**
	 * Returns a list of the tables in the database.
	 *
	 * @return array
	 */
	public function listTables()
	{
		$this->_connect();
		return $this->_serverType->listTables();
	}

	/**
	 * Returns the column descriptions for a table.
	 *
	 * The return value is an associative array keyed by the column name,
	 * as returned by the RDBMS.
	 *
	 * The value of each array element is an associative array
	 * with the following keys:
	 *
	 * SCHEMA_NAME      => string; name of database or schema
	 * TABLE_NAME       => string;
	 * COLUMN_NAME      => string; column name
	 * COLUMN_POSITION  => number; ordinal position of column in table
	 * DATA_TYPE        => string; SQL datatype name of column
	 * DEFAULT          => string; default expression of column, null if none
	 * NULLABLE         => boolean; true if column can have nulls
	 * LENGTH           => number; length of CHAR/VARCHAR
	 * SCALE            => number; scale of NUMERIC/DECIMAL
	 * PRECISION        => number; precision of NUMERIC/DECIMAL
	 * UNSIGNED         => boolean; unsigned property of an integer type
	 * PRIMARY          => boolean; true if column is part of the primary key
	 * PRIMARY_POSITION => integer; position of column in primary key
	 *
	 * @todo Discover integer unsigned property.
	 *
	 * @param string $tableName
	 * @param string $schemaName OPTIONAL
	 * @return array
	 */
	public function describeTable($tableName, $schemaName = null)
	{
		$this->_connect();
		return $this->_serverType->describeTable($tableName, $schemaName);
	}

	/**
	 * Inserts a table row with specified data.
	 * Special handling for PDO_IBM
	 * remove empty slots
	 *
	 * @param mixed $table The table to insert data into.
	 * @param array $bind Column-value pairs.
	 * @return int The number of affected rows.
	 */
	public function insert($table, array $bind)
	{
		$this->_connect();
		$newbind = array();
		if (is_array($bind)) {
			foreach ($bind as $name => $value) {
				if($value !== null) {
					$newbind[$name] = $value;
				}
			}
		}

		return parent::insert($table, $newbind);
	}

	/**
	 * Adds an adapter-specific LIMIT clause to the SELECT statement.
	 *
	 * @param string $sql
	 * @param integer $count
	 * @param integer $offset OPTIONAL
	 * @return string
	 */
	public function limit($sql, $count, $offset = 0)
	{
		$this->_connect();
		return $this->_serverType->limit($sql, $count, $offset);
	}

	/**
	 * Gets the last ID generated automatically by an IDENTITY/AUTOINCREMENT
	 * column.
	 *
	 * @param string $tableName OPTIONAL
	 * @param string $primaryKey OPTIONAL
	 * @return integer
	 */
	public function lastInsertId($tableName = null, $primaryKey = null)
	{
		$this->_connect();

		if ($tableName !== null) {
			$sequenceName = $tableName;
			if ($primaryKey) {
				$sequenceName .= "_$primaryKey";
			}
			$sequenceName .= '_seq';
			return $this->lastSequenceId($sequenceName);
		}

		$id = $this->getConnection()->lastInsertId();

		return $id;
	}

	/**
	 * Return the most recent value from the specified sequence in the database.
	 *
	 * @param string $sequenceName
	 * @return integer
	 */
	public function lastSequenceId($sequenceName)
	{
		$this->_connect();
		return $this->_serverType->lastSequenceId($sequenceName);
	}

	/**
	 * Generate a new value from the specified sequence in the database,
	 * and return it.
	 *
	 * @param string $sequenceName
	 * @return integer
	 */
	public function nextSequenceId($sequenceName)
	{
		$this->_connect();
		return $this->_serverType->nextSequenceId($sequenceName);
	}

	/**
	 * Retrieve server version in PHP style
	 * Pdo_Idm doesn't support getAttribute(PDO::ATTR_SERVER_VERSION)
	 * @return string
	 */
	public function getServerVersion()
	{
		try {
			$stmt = $this->query('SELECT service_level, fixpack_num FROM TABLE (sysproc.env_get_inst_info()) as INSTANCEINFO');
			$result = $stmt->fetchAll(Zend_Db::FETCH_NUM);
			if (count($result)) {
				$matches = null;
				if (preg_match('/((?:[0-9]{1,2}\.){1,3}[0-9]{1,2})/', $result[0][0], $matches)) {
					return $matches[1];
				} else {
					return null;
				}
			}
			return null;
		} catch (PDOException $e) {
			return null;
		}
	}
}
